Rolling mill roll drives



Oct. 10, 1967 P. M. LOWY 3,345,849

ROLLING MILL ROLL DRIVES Filed Sept. 10, 1964 INVENTOR Paul M. Lowy United States Patent 3,345,849- RULLING MILL ROLL DRIVES Paul M. Lowy, Pittsburgh, Pa., assiguor to Mesta Machine Company, a corporation of Pennsylvania Filed Sept. 10, 1964, Ser. No. 395,455 4 Claims. (Ci. 72249) This invention r lates to rolling mill roll drives and more particularly to an inching drive for positioning a drive half coupling for a roll by rotating the coupling automatically to position it to receive the roll half coupling.

In a rolling mill it is necessary to make frequent changes of work rolls'as they become worn or their surfaces become scored. To make these changes rapidly it is a general practice to provide a coupling between the work roll shaft and the drive shaft. This coupling is of a well-known type which requires only axial movement of the work roll or drive shaft or both to perform coupling or uncoupling. The coupling consists of two parts; one part called the drive half which is attached more or less permanently to the drive shaft and another part called the roll half which is attached more or less permanently to the work roll shaft. When a new roll and its coupling half are being inserted into the mill it is necessary to align the two coupling halves with respect to'their angular position about the axis of rotation in order to insure proper mating of the coupling halves. This requires that either the roll half coupling or the drive half coupling be rotated to properly position the coupling halves. In the past this could be done only by manual means and by trial and error rotation of the drive until the coupling halves were aligned. This practice is wasteful of time and effort and in the light of the frequent roll changes required during a given days operation results in a serious loss of productive time and efiiciency.

I have invented a means for overcoming this problem.

The structure of my invention permits rapid roll changes without manual efiort and without hunting and overshooting characteristic of. prior practices.

In a preferred embodiment of my invention, I provide in a rolling mill having a driven roll, a main drive motor, a driveshaft, and a coupling half on the drive shaft receiving a coupling half on the driven roll, an inching drive means, clutch means selectively connecting the inching drive means and the drive shaft on the main drive means, a first proximity switch means contacted by said drir e coupling at an angular position adjacent the loading position and adapted to initiate a jogging circuit, a jogging circuit which regularly interrupts the flow of energy to the positioning drive means in such a way that the coupling is rotated by small intermittent angular increments, and a second proximity switch at the loading position adapted to disconnect the positioning means.

In the foregoing general description I have set out certain objects, advantages and purposes of my invention. Other objects, advantages and purposes will be apparent from a consideration of the following description and the accompanying drawings in which:

FIGURE 1 is a top plan View of a rolling mill incorporating my invention. For completeness two duplicate sets of positioning apparatus are shown, one for each of the two work rolls of a typical mill. In the description that follows only one of the sets of apparatus will be described, the operation of the other being identical.

FIGURE 2 is a top plan view of the positioning means of my invention;

FIGURE 3 is a section on the line IIIIII of FIGURE 1 showing the proximity switches; and

FIGURE 4 is a schematic drawing of the electrical control circuit of my invention.

Referring to the drawings, I have illustrated in FIGURE 1 a roll stand 10 having work rolls 11 and a drive motor 12, gear box 13 and drive shaft 14 for each work roll. The coupling is made up of two halves, a roll half 14:: and a drive half 14b.

The positioning means is shown in FIGURE 1 attached to the far end of the driving means for the drive shaft, inthis case an electric motor. The location shown for the attachment of the positioning means is for illustrative purposes and does not limit the scope of this invention, it being understood that said positioning means could be attached at any point intervening between the point of attachment shown and the coupling 14b by means well known in the art,

The positioning means shown in FIGURE 2, consisting of a motor 22 connected to a clutch-brake 23, such as a Sommer Drive, in turn connected to a gear reducer 20, is selectively coupled to the far end of drive motor 12 by means of air clutch 21. The clutch 21 engages and disengages the reducer 20 with the end of the drive motor 12. A first proximity switch 24 is placed at the drive coupler shaft 25 at an angular position near but spaced from the desired load position, i.e. the angular alignment of drive half coupling with roll half coupling. A second proximity switch 25 is placed at the load position to be contacted by the drive coupler shaft 25 to stop the coupling 14b in the load position. i

The device of this invention is operated in the following manner. When it is desired to change the rolls of a mill equipped with this invention, the drive motor 12 is stopped by disconnecting it electrically from its power supply. The work roll is removed by withdrawing the roll axially from the roll stand as described in Kalberkamp application Serial No. 238,361, now Patent No. 3,204,443, or in any other manner. The start switch 27 on the positioning gear motor 22 is closed starting the motor and energizing the operating coil 33 of the air clutch 21. An electrical interlock 34 of conventional form is provided such that switch 27 cannot be actuated to start motor 22 unless the power to drive motor 12 is disconnected since electrical interlock 34 is a contact of a relay (not shown) whose coil is connected across the input terminals of the motor 12. This causes the drive coupler shaft 25 to be rotated at rated motor speed for motor 22 until the first proximity switch 24 is contacted by a control member 28 on the drive coupler shaft. When the first proximity switch is contacted and opened, the jogging circuit is initiated.

The jogging circuit consists of a pulsing device T which energizes and deenergizes the operating coil 30 of the clutch-brake 23 and the operating coil 31 of the brake associated with clutch-brake 23. The pulsing device can be of any type which gives repeated interruptions of current at a fixed rate. For illustration a vibrating relay is shown. The vibrating relay has normally closed contacts 32 in series with its own operating coil giving the familiar doorbell action. Additional contacts 29 actuated together with contacts 32 provide the interruptions of current to operating coils 30 and 31.

The interruptions of current to operating coils 30 and 31 alternately energize and deenergize the clutchq. brake 23 in conjunction with release and application of the brake associated with clutch-brake 23.

The alternate energizing and deenergizing of the clutch in conjunction with release and application of the brake allows motor 22 to apply high torques for extremely short time intervals to the high inertia load represented by the armature of the drive motor 12 and the gearing 13. By this means fine increments of angular motion of the order of of a revolution can be applied to the drive shaft to assure accurate stopping. When the positioning drive has rotated the shaft 25 until the second proximity switch 26 is opened by the control member 28, the positioning motor 22 stops and the air clutch 21 is deenergized leaving the coupling half 1412 in proper alignment to receive the coupling half 14a on the work roll.

The new work rolls are positioned by a template (not shown) to the proper entry position and inserted so that coupling halves 14a and 14b interfit without further movement or alignment.

While I have illustrated a presently preferred embodiment of my invention, it will be understood that this invention may be otherwise embodied within the scope of the following claims.

I claim:

1. In a rolling mill having a driven roll, a main drive motor having a driven shaft and a half coupling operatively connected to the drive motor shaft receiving an interfitting half coupling on the driven roll, the improvement comprising inching drive means, clutch means selectively connecting the inching drive means and the main drive mo. tor, a source of power for said drive means, a first switch means contacted by means driven by the drive motor shaft and moving with the said half coupling at a position adjacent and spaced from a selected load position, a circuit capable of providing timed power impulses from said source of power for said inching drive means actuated by the first switch means, a second switch means at the load position adapted to disconnect the power source from said inching drive means.

2. In a rolling mill having a driven roll, a main drive motor having a driven shaft and a half coupling operatively connected to the main drive motor shaft receiving an interfitting half coupling on the driven roll, the improvement comprising inching drive means, clutch means selectively connecting the inching drive means and the main drive motor, a source of power for said drive means, a first switch means contacted by means driven by the drive motor shaft at a position adjacent and spaced from a selected load position, a circuit capable of providing timed power impulses from said source of power for said inching drive means actuated by the first switch means, interlock means preventing said circuit from operating so long as the main drive motor receives power, a second switch means at the load position adapted to disconnect the power source from said inching drive means.

3. In a rolling mill having a driven roll, a main drive motor having a driven shaft and a half coupling operatively connected to the drive motor shaft receiving an interfitting half coupling on the driven roll, the improvement comprising inching drive means, clutch means selectively connecting the inching drive means and the main drive motor, brake means on said inching drive means, a source of power for said drive means, a first switch means contacted by means on the drive motor shaft at a position adjacent and spaced from a selected load position, a circuit capable of providing alternately timed power impulses from said source of power to said inching drive means and to said brake means and actuated by the first switch means, a second switch means at the load position adapted to disconnect the power source from said inching drive means.

4. A structure as claimed in claim 1 wherein the circuit capable of providing timed power is interlocked with a power source for the main drive motor in such manner that said circuit is inoperative when said main drive motor is receiving power.

References Cited UNITED STATES PATENTS 1,950,573 3/1934 Schreck 72238 2,839,138 6/1958 Wilhelm 226-134 2,911,804 11/1959 OBrien 72-249 3,293,898 12/1966 Thomas et a1 72249 RICHARD J. HERBST, Primary Examiner.

A. RUDERMAN, Assistant Examiner. 

1. IN A ROLLING MILL HAVING A DRIVEN ROLL, A MAIN DRIVE MOTOR HAVING A DRIVEN SHAFT AND A HALF COUPLING OPERATIVELY CONNECTED TO THE DRIVE MOTOR SHAFT RECEIVING AN INTERFITTING HALF COUPLING ON THE DRIVEN ROLL, THE IMPROVEMENT COMPRISING INCHING DRIVE MEANS, CLUTCH MEANS SELECTIVELY CONNECTING THE INCHING DRIVE MEANS AND THE MAIN DRIVE MOTOR, A SOURCE OF POWER FOR SAID DRIVE MEANS, A FIRST SWITCH MEANS CONTACTED BY MEANS DRIVEN BY THE DRIVE MOTOR SHAFT AND MOVING WITH THE SAID HALF COUPLING AT A POSITION ADJACENT AND SPACED FROM A SELECTED LOAD POSITION, A CIRCUIT CAPABLE OF PROVIDING TIMES POWER IMPULSES FROM SAID SOURCE OF POWER FOR SAID INCHING DRIVE MEANS ACTUATED BY THE FIRST SWITCH MEANS, A SECOND SWITCH MEANS AT THE LOAD POSITION ADAPTED TO DISCONNECT THE POWER SOURCE FROM SAID INCHING DRIVE MEANS. 